1. Technical Field
The present invention relates to magnetic worktables for use with machine tools, and more particularly, to a magnetic worktable modularized and capable of being flexibly adjusted to operate.
2. Description of Related Art
In general, machine tools, such as lathes, milling machines, grinding machines, and all-in-one processing machines, each comprise a worktable for positioning a workpiece to be processed and mounting a vise or a jig whereby the workpiece is fixed to the worktable.
Not only can a conventional worktable have its workpiece fixed in place under a mechanical force, but a commercially available worktable also can have its workpiece fixed thereto by magnetic attraction under a magnetic force. For example, Taiwan invention Patent M350429 provides a load-carrying platform having therein multiple rows of magnetic assemblies, wherein a current entering the magnetic assemblies is controlled in a manner to generate a magnetic field between two adjacent rows of magnetic assemblies, thereby allowing a workpiece to be attached to the magnetic assemblies. However, the magnetic assemblies have to be present throughout the load-carrying platform, and thus the magnetic worktable incurs a high manufacturing cost.
Another commercially available magnetic worktable comprises a worktable body and a plurality of magnetic devices fixed to the worktable body at appropriate locations thereof, respectively, wherein the magnetic devices admit a current and thereby generate a magnetic attraction force under which a workpiece is fixed to the magnetic devices by magnetic attraction. The magnetic devices have the same structure as the aforesaid ones but have smaller dimensions than the aforesaid ones, thereby allowing the workpiece to be attached to the magnetic devices by a smaller area. Although the magnetic worktable incurs a relatively low manufacturing cost, the magnetic devices are scanty and have invariable positions; as a result, the magnetic devices are only applicable to workpieces of specific shapes and dimensions, thereby compromising the practicability of the magnetic worktable. Furthermore, the magnetic devices have to be electrically connected to rectifiers, respectively, and subjected to current control, respectively; as a result, the circuit and control method of the magnetic worktable are intricate and power-inefficient.